Anyone installed a TentLabs XO on an Arcam Alpha 5 Plus Player

[dewdrop]

Hi there,
I am interested in improving the sound of my player. I have looked at the Arcam A. 5 Plus service manual and noticed I can tap the 5 V to supply to the TentLabs XO, is this advisable?

Anyone out there to share his experience is most welcome!

Cheers,

[jean-paul]

Modded a Alpha 5 some time ago and I ran into the same problem. Difference is that I used the plain Tent module. I just tell my experiences, maybe they are of some use to you.

It is a *very* nice cdplayer but because of the riser board placing a low jitter clock the right way ( short wires, not enough space for a separate supply etc ) is difficult. A second inconvenience for placing the clock is that some parts of the cdplayer are always on. With a Tent XO 2 with its own supply I would have to make the choice to leave the XO 2 continuously on or I would have had
to make a supply that also switches on when the power button is pushed. I mailed Guido and he assured me that the XO can be powered continuously.

Because of time constraints I ended up soldering the XO module at the spot where the original crystal was ( I drilled the right holes with a 1 mm drill ) and I used the main 5V on the riserboard via a choke. I soldered an OSCON directly on the pins of the Tent XO. results were reasonably OK. There was improvement but not as usual. There was stray RF because of the new clock on the riserboard and a shield was made by the owner to place between the mainboard and the riserboard. All this did not deserve a prize.

The next Alpha 5 will definitely have an separate supply with a separate transformer as usual. The separate supply will then be mounted on the rear panel.

[dewdrop]

Hi Jean-Paul,
Are you saying that the improvement is only marginal with the XO1 module?

Cheers,
Ed

[jean-paul]

Soldering just the module without its own supply gives an improvement ( in *this* cdplayer ) that is less than optimal because of the particular environment. Please read: it can be done a lot better. Tapping the switched 5V that also feeds the SAA is not the-right-way as that line is polluted because of the SAA.

Please consider a separate supply and transformer for the module. If you design a small pcb with a power transformer that can be mounted at the rear panel you won't regret it for sure. You will need to use shielded cable because of the length. Adding an iron shield under the riserboard with the same dimensions as the riserboard will improve things.

If you check the riserboard you'll see that there is room for drilling 3 mm holes for mounting a shield with metal standoffs. Draw the holes and drill them with the riserboard out of the cdplayer. Now draw the holes on the metal sheet you've just cut. Be sure to lift the riserboard gently in a straight manner. Don't remove the riserboard to often. Mod the thing and leave it like it is when it's ready. The contacts aren't designed for dismounting many times.

In all cases mounting just the module ( and feeding it from the cdplayers 5V ) gives less good results than feeding the module with its own supply. A separate transformer is the icing on the cake with the bonus that you won't run in to groundloops. There are some threads about this.

Good luck with modding that nice Arcam.

Regards,

Jean-Paul

[t.]

Hi Jean-Paul

I also have an Alpha5+, I have done a few mods to, zero oversampling,double crown dac added, Multicap RTX coupling caps and mainly Elna Starget caps on Audioboard.
I have recently tried a Kwack clock7 with its own supply but I'm unsure about the results.
Do you have any more tips or mods I could try that will improve this cdp?

Kind Regards

Ron

[dewdrop]

Hi Ron,
Can you share a bit of information regarding your zero oversampling and the double crown DAC mods? Did they improve the performance?

[t.]

Originally posted by dewdrop
Hi Ron,
Can you share a bit of information regarding your zero oversampling and the double crown DAC mods? Did they improve the performance?

Hi ED

Well in my opinion the double crown dac is alot better than the standard A version and I prefer zero over-sampling as well, at the minute I'm just trying a few different mods and what ever ones I like I leave in, I'm hoping some one with experience with these players can give us a few tips
The one Jean-Paul said regarding putting a shield under the Audioboard sounds a good idea.
I tried a clock7 before in a Marantz cd67, it worked very well in that but does not seem to suit the Alpha5+, I found it made it sound artificial so I'm just powering the standard internal clock with its own supply which seemed better in this player.
All the mods I have done at the minute are

Added double crown dac.
Zero-oversampling.
Added 4.7uf Sanyo Oscon SG bypasses to pins 13 & 18 msb pins of dac.
changed all 1000uf caps to Panasonic NHG.
cut pcb tracks between 2 and 4 of dac and connected pin 4 of dac to pin 9 of SAA7220.
removed muting transistors.
changed c8/108 to 100uf blackgate N types.
Changed coupling caps to 1uf Multicap RTX.
Changed all 100uf caps on Audioboard to Elna Stargets, some are bypassed with 1uf Wima's.
Given the clock its own supply using 12v transformer, 11dq10 diodes, 2200uf fc,LM7805,8200uf Panasonic FC.
All four op-amps are OP27's, I'm thinking about building a circuit around AD844

Regards
Ron

[guido]

Originally posted by t.

...
cut pcb tracks between 2 and 4 of dac and connected pin 4 of dac to pin 9 of SAA7220.
...

Regards
Ron

Ron, i had a few beers tonight, but i still think something's wrong here. Pin 4 of the A version of the 1541 is NOT used with i2s. This is only SCK with the plain version. You are still using BCK (pin2) for input latching and also to generate internal LE signal for output latching.

The 7220 pin 9 is 11,2896MHz anyway. With your non-os version where the DAC is connected to the 7210 the bitclock should be:
44.1kHz * 32 * 2 = 2.8224 MHz.

But maybe i had too many beers....

Greetings,

[Guido Tent]

Originally posted by dewdrop
Hi Jean-Paul,
Are you saying that the improvement is only marginal with the XO1 module?

Cheers,
Ed

dear all,

Make sure the XO is powered with LOW noise 5V. Tapping a 5V supply from the player will yield disappointing results, so build a seperate supply of which you are sure about the noise performance, or buy an XO2........

cheers

[t.]

Originally posted by guido


Ron, i had a few beers tonight, but i still think something's wrong here. Pin 4 of the A version of the 1541 is NOT used with i2s. This is only SCK with the plain version. You are still using BCK (pin2) for input latching and also to generate internal LE signal for output latching.

The 7220 pin 9 is 11,2896MHz anyway. With your non-os version where the DAC is connected to the 7210 the bitclock should be:
44.1kHz * 32 * 2 = 2.8224 MHz.

But maybe i had too many beers....

Greetings,

Hi Guido

Thank you for your reply, I got this mod from a guy on Audioasylum who tried this with a Alpha5 so I tried it with mine, I'm sure it made a difference and sounded better so I just left it in, since then I have added the crown dac.
Do diiferent clocks work better with different dacs? I was surprised the clock7 made my Alpha5+ sound worse yet it improved the Marantz cd67, do you have any tips or advice we could try to improve things? my cdp don't sound bad but I'm sure there is room for improvement
Would one of your clocks be better suited to this cdp? I have the diagram if your interested in having a look

Kind Regards,

Ron